id,summary,reporter,owner,description,type,status,component,version,severity,resolution,keywords,cc,stage,has_patch,needs_docs,needs_tests,needs_better_patch,easy,ui_ux
19095,Dubious code in multiple_database tests,aaugustin,nobody,"`QueryTestCase.test_o2o_cross_database_protection` contains code that seems invalid to me.
In that test, `UserProfile` has a nullable one-to-one relation to `User`.
An unsaved instance of `User` called `charlie` is created at line 655, and a profile is attached to this instance at line 664: `charlie.userprofile = bob_profile`.
But after saving everything, that doesn't work as expected: the profile isn't linked to the user!
This is easy to understand: this line basically performs `bob_profile.user_id = charlie.id` (and populates relation caches); but since `charlie` is unsaved, `charlie.id` is `None`, hence `bob_profile.used_id` remains `None`.
I'm attaching a patch for this test case that reloads the objects and tests that `charlie.userprofile == bob_profile` ; with this patch, the test fails, proving my point.
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In #18153, I tried to catch such programming errors by raising an exception. And that breaks that test.
I think this code needs to fixed, while preserving as much of the testing behavior as possible.",Bug,closed,"Database layer (models, ORM)",master,Normal,fixed,,,Unreviewed,0,0,0,0,0,0